Question: How are wildfires connected to climate change?

Answer: Wildfires, while not strictly ‘weather’ events themselves, are certainly affected by weather. Climate change itself cannot cause a wildfire, but can increase the likelihood that one will start, and that if it does, it will be more intense, widespread and long-burning. [1]

Global warming magnifies the threat of wildfires in two ways. First, snow melts earlier in the spring but then starts to fall later in the autumn. This extends the dry season, allowing forests to dry out sooner and for a longer time. Second, global warming increases the frequency and duration of heat waves that intensify and expand dry conditions, turning green vegetation into easily ignited tinder. [2,3,4,5]

Over the last three decades, the number of wildfires in the U.S. has not changed much, but the acreage burned from those fires has increased significantly. [6] This is despite better forest management and fire suppression policies that should decrease the acreage burned by wildfires. The fact that the opposite is true strongly suggests that the impact of climate change is outrunning efforts to mitigate the damage, rising costs and danger to human life that we are bearing from wildfires.

So, what’s the bottom line? There is strong evidence that destruction from wildfires across the U.S. has nearly doubled over the last 30 years, and that trend is consistent with a longer fire season exacerbated by higher seasonal temperatures due to global warming. The impact of climate change on wildfires is costing us billions.